The 1703 Creators Update resets some settings and registry changes. Here are some examples I've run across that were undone:
- Right context menu "Move to folder" as detailed at https://www.howtogeek.com/howto/windows/add-copy-to-move-to-to-the-windows-explorer-right-click-menu/
- Remap Caps Lock to Inactive using https://sharpkeys.codeplex.com/
- Un-checking Fast Startup to prevent boot problems as detailed at http://answers.microsoft.com/en-us/insider/forum/insider_wintp-insider_devices/windows-10-final-build-black-screen-after-boot/6c216e14-a112-461e-9faa-62594e195b13
It is not clear whether such changes are a feature or a bug - for example it is not clear whether the boot problems in #3 have been fixed.
Certain other customizations are not changed by the Creators Update. As an example, getting the taskbar clock to show seconds as detailed at http://winaero.com/blog/taskbar-clock-show-seconds-windows-10/ is unaffected by the update.
Presumably there are many other customizations that are changed other than the 3 I noted.
